In subsea hydrocarbon well applications, production tubing may be used in a subsea well for communicating produced well fluids from subterranean formations to equipment at the sea floor. Completing a subsea well and installing the production tubing includes lowering production tubing into a marine riser string that extends from a surface platform (e.g. a surface vessel) down to the subsea equipment (e.g. a well tree, a blowout preventer (BOP), and/or other subsea equipment) that defines the sea floor entry point of the well. The marine riser string forms protection for the production tubing and other equipment which is lowered into the subsea well from the platform.
At the sea surface, the top end of the production tubing is connected to (e.g. threaded to) a tubing hanger that follows the production tubing down through the marine riser string. A tubing hanger running tool is connected between the tubing hanger and a landing string, and the landing string is lowered down the marine riser string to position the tubing hanger running tool, tubing hanger, and production tubing in the well so that the tubing hanger lands in, or becomes seated in, the subsea well head. The tubing hanger running tool is hydraulically or mechanically activated to set the tubing hanger in the well tree. The setting of the tubing hanger locks it to the well tree. The tubing hanger running tool may then be remotely unlatched from the tubing hanger and retrieved with the landing string from the platform.